Datasheet

LTC4155
32
4155fc
OPERATION
Figure 7. Battery Charger Flow Chart
Figure 8. Standard Thermistor Network
CLEAR LOW BATTERY
AND SAFETY TIMERS
NTC OUT-OF-RANGE
INDICATE NTC FAULT
CHARGE AT
CONSTANT CURRENT
PAUSE SAFETY TIMER
PAUSE SAFETY TIMER
CHARGE AT
FIXED VOLTAGE
RUN SAFETY TIMER
RUN LOW BATTERY TIMER
POWER AVAILABLE
TIMER > 30 MINUTES
SAFETY TIMER
EXPIRED
V
BAT
> 2.8V V
BAT
< V
RECHRG
I
BAT
< C/x
NO
NO YES
YES
YES
YES
YES
YES
NO
NO
V
BAT
> V
FLOAT
– J V
BAT
< 2.8V
2.8V < V
BAT
< V
FLOAT
– J
NO
NONO
STOP CHARGING STOP CHARGING
INDICATE BATTERY FAULT
V
BAT
RISING
THROUGH V
RECHRG
BAT FALLING
THROUGH V
RECHRG
INDICATE CHARGING
STOPPED
INDICATE CONSTANT
VOLTAGE, I < C/x
4155 F07
NO
YES
YES
TIMER IN 8 HOUR -
C/x MODE
NO
YES
V
BAT
INDICATE
CONSTANT CURRENT
INDICATE CONSTANT
VOLTAGE, I > C/x
INDICATE LOW CELL VOLTAGE
TRICKLE CHARGE (8%)
R
NTC
R
BIAS
LTC4155
4155 F08
NTC
NTCBIAS
T